The class of polymers of carbon monoxide and olefin(s) has been known for some time. Brubaker, U.S. Pat. No. 2,495,286, produced such polymers of relatively low carbon monoxide content in the presence of free radical initiators, e.g., peroxy compounds. G.B. 1,081,304 produced similar polymers of higher carbon monoxide content in the presence of alkylphosphine complexes of palladium salts as catalyst. Nozaki extended the reaction to produce linear alternating polymers in the presence of arylphosphine complexes of palladium moieties and certain inert solvents. See, for example, U.S. Pat. No. 3,694,412.
More recently, the class of linear alternating polymers of carbon monoxide and at least one ethylenically unsaturated hydrocarbon has become of greater interest in part because of the greater availability of the polymers. The more recent processes for the production of the linear alternating polymers, now known as polyketones or polyketone polymers, are illustrated by a number of published European Patent Applications including 121,965, 181,014, 213,671 and 257,663. The processes generally involve the use of a catalyst composition formed from a compound of palladium, cobalt or nickel, the anion of a strong non-hydrohalogenic acid and a bidentate ligand of phosphorous, arsenic or antimony. Without wishing to be limited, preferred catalyst compositions are formed from a compound of palladium, the anion of a non-hydrohalogenic acid having a pKa below 2 and a bidentate ligand of phosphorus.
Even more recently, catalyst compositions have been employed which include diphosphine complexes of a hydrocarbylpalladium halide salt. In copending U.S. patent application Ser. No. 433,871, filed Nov. 9, 1989, the use of a diphosphine/hydrocarbylpalladium halide complex is disclosed as a catalyst composition for the production of the linear alternating polymers. Although such complexes give good results when employed as the catalyst composition, it would be of advantage to provide additional catalyst compositions useful in the preparation of linear alternating polymers of carbon monoxide and at least one ethylenically unsaturated hydrocarbon.